Proliferation inhibition and apoptosis induction of human leukemic K562 cells by ubiquitin isopeptidase inhibitor Ⅰ / 白血病·淋巴瘤

ABSTRACT

Objective To investigate the effects of ubiquitin isopeptidase inhibitor Ⅰ on proliferation and apoptosis of human leukemic K562 cells.Methods Human leukemic K562 cells were treated with different concentration of ubiquitin isopeptidase inhibitor Ⅰ.Cell proliferation was monitored by MTT assay.Cell apoptosis was analyzed by flow cytometry after Annexin V/PI staining,and mRNA expression levels of bcl-2,bax and Caspase-3 were quantified by reverse transcription-polymerase chain reaction (RT-PCR).Results MTT assay showed that the proliferation of K562 cells was markedly inhibited by ubiquitin isopeptidase inhibitor Ⅰ in a time-and-dose dependent manner.The Annexin V positive rate of K562 cells after treatment with ubiquitin isopeptidase inhibitor Ⅰ was significantly increased by FCM analysis (P ＜ 0.05).The early apoptosis rate of K562 cells treated with 100 nmol/L ubiquitin isopeptidas inhibitor Ⅰ by 72 h,was obviously increased compared to control cells [(15.4±1.3) ％ vs (4.1±0.9) ％,P ＜ 0.01].The mRNA levels of Caspase-3 and bax were up-regulated and bcl-2 was down-regulated after treated with ubiquitin isopeptidase inhibitor Ⅰ,and the differences were statistically significant from control cells (P ＜ 0.05).Conclusion Ubiquitin isopeptidase inhibitor Ⅰ has inhibitory effect on proliferation and inductive effect on apoptosis of K562 leukemia cells,implying its possible application in treating leukemia.